What to use for exhaust pipe?

[longlongtimeago]

I have to build a couple of exhaust systems in the near furure. What do we get pipe the correct size...how do you bend it?

 

[Shane5684]

I have to build a couple of exhaust systems in the near furure. What do we get pipe the correct size...how do you bend it?[/QUOTE

I use a pipe bender or I make jigs for the press. Also using 316L stainless 3/4 for my intake and 3/4 316L heavy walled water pipe for the exhaust. Used calipers to measure the port size then went from there and matched it up.

 

[DaddyJohn]

I use bits of other power equipment exhaust, old handlebars, random tubing, etc. That said, I’m no restorationist…

 

[nightgrider]

A manual bender is pretty cheap and would allow you to make nice bends easily. As long as you don't restrict exhaust flow by having too small ID of tubing or pipe, you'll be good.

https://www.ebay.com/itm/VEVOR-Pipe...2349624.m46890.l49286&mkrid=711-127632-2357-0

 

[longlongtimeago]

I have never needed to but tube this small...where can you buy it? Is this a home depot kinda thing?

 

[nightgrider]

I use bits of other power equipment exhaust, old handlebars, random tubing, etc. That said, I’m no restorationist…

Like @DaddyJohn said using pieces of other pre-bent tubing or pipe works well too. I myself found a geriatric toilet seat frame at local goodwill for cheap that had some nice bends along with part of an old picnic table leg. That I eventually plan to use to make an exhaust.

 

[nightgrider]

I have never needed to but tube this small...where can you buy it? Is this a home depot kinda thing?

Home depot will be pretty limited, mostly they have iron black pipe, emt conduit, and rigid conduit. The 1/2" or 3/4" conduit would probably work fine for exhaust. But before you weld it you need to remove the galvanized finish. Otherwise the heat will release toxic fumes.

 

[nightgrider]

I have never needed to but tube this small...where can you buy it? Is this a home depot kinda thing?

A steel fabrication supplier would have the largest selection of tubing.

 

[Shane5684]

McMaster Carr or metals depot

 

[Charles S]

A manual bender is pretty cheap and would allow you to make nice bends easily. As long as you don't restrict exhaust flow by having too small ID of tubing or pipe, you'll be good.

https://www.ebay.com/itm/VEVOR-Pipe...2349624.m46890.l49286&mkrid=711-127632-2357-0

Initially, I misread that as: "A mandrel bender is pretty cheap..." and nearly choked...

 

[Charles S]

Search "mandrel bends" and/or "mandrel bent tubing". You can buy pre-bent sections and piece an exhaust together. Buy a couple of 180 degree bends and you can slice and dice all kinds of bends. Mandrel bent tubing is best for exhaust because it maintains its size in the bends. Choose a size with ID as close as possible to the size of your engine's exhaust port.

 

[Shane5684]

You can also use “pie wedges “ but it’s very time consuming.

 

[desert rat]

I found a tube bending company and they let me go through there scrap bins and sold what I pulled out for scrap price, I used stainless 3/4"

 

[Shane5684]

I found a tube bending company and they let me go through there scrap bins and sold what I pulled out for scrap price, I used stainless 3/4"

That’s a very nice job.

 

[EricD..]

How about a Robertson Torque tube. Not too expensive https://www.robertsonstorquetubes.com/minibikes

 

[Charles S]

I found a tube bending company and they let me go through there scrap bins and sold what I pulled out for scrap price, I used stainless 3/4"

Nice!

 

[ole4]

I use 1" stainless tube. I get it at Metals are us which is local to my area. I have a tube bender so it is pretty easy to make them. I use a tig welder to weld them but if you have a gas mig welder you can get a spool of stainless wire and weld with it. I have had some issues with not being able to bend a real tight radius so I find prebent 90 bends on ebay.

 

[SAS289]

Home depot will be pretty limited, mostly they have iron black pipe, emt conduit, and rigid conduit. The 1/2" or 3/4" conduit would probably work fine for exhaust. But before you weld it you need to remove the galvanized finish. Otherwise the heat will release toxic fumes.

I did a short header pipe with 3/4" conduit. Taking the galvanized off with muriatic acid was a bit scary. I did it on a windless day outside with a fan blowing the fumes away from me. Had a fairly violent chemical reaction when the pipe was put into the pan.

 

[Skipp]

If I remember correctly HavasuDave used either a bicycle or motorcycle handlebar for a really cool exhaust on a side popper

 

[Shane5684]

I use 1" stainless tube. I get it at Metals are us which is local to my area. I have a tube bender so it is pretty easy to make them. I use a tig welder to weld them but if you have a gas mig welder you can get a spool of stainless wire and weld with it. I have had some issues with not being able to bend a real tight radius so I find prebent 90 bends on ebay.

Are you purging it as you weld?